Crud Ring with zero powder
#1
Thread Starter
Banned
Joined: Dec 2008
Posts: 9,186
Likes: 0
From: Boncarbo,Colorado
So when i was testing out the Winchester W209 primers in the Wolf, I mainly wanted to see how bright and how long the flame was that came out the end of the barrel just by using a primer. After popping 6 primers i went to run a patch down the bore to remove the fouling and was shocked to see a crud ring forming 2" in front of the Breech plug just by using primers 

That was interesting as i never would have thought that just a primer could start a crud ring. And WHY only in that spot so consistently?
Zero oil of any kind in the bore during this test.


That was interesting as i never would have thought that just a primer could start a crud ring. And WHY only in that spot so consistently?
Zero oil of any kind in the bore during this test.
#2
Nontypical Buck
Joined: Feb 2003
Posts: 2,722
Likes: 0
From: Kerrville, Tx. USA
Probably has to do with how the flame gets dispersed through the flame channel. With powder in place, it probably won't be an issue. When you passed a patch, was there a tight spot there, or was this cosmetic only and not a narrowing issue?
#7
I suspect that the primer material is some kind of a composition that's made from lead styphnate.
The pure form is a crystal that looks like a brown powder so I suspect that what is used in primers isn't pure.
So maybe that's what creates some of the residue.
And different companies have slightly different primer formulas that make a difference in the type and amount of residue.
The primers are mass produced while the primer material is in a liquid state that acts as a carrier for the active ingredient. So some of the impurities are probably necessary to make mass production possible.
http://en.wikipedia.org/wiki/Lead_styphnate
http://www.powerlabs.org/chemlabs/lead_styphnate.htm
14 second video:
http://www.youtube.com/watch?v=IGnTJqh55H0
The pure form is a crystal that looks like a brown powder so I suspect that what is used in primers isn't pure.
So maybe that's what creates some of the residue.
And different companies have slightly different primer formulas that make a difference in the type and amount of residue.
The primers are mass produced while the primer material is in a liquid state that acts as a carrier for the active ingredient. So some of the impurities are probably necessary to make mass production possible.
http://en.wikipedia.org/wiki/Lead_styphnate
http://www.powerlabs.org/chemlabs/lead_styphnate.htm
14 second video:
http://www.youtube.com/watch?v=IGnTJqh55H0
Last edited by arcticap; 12-29-2011 at 09:36 AM.
#9
Even though the surface of the bore may have been cleaned with alchohol the pores of the metal still contain contaminates with can react with the heat of a primer as well as the heat of the load.
I wonder if he were to clean the bore with boiling water, which will case the pores in the metal to purge their contents then try the same experiment, what the results might be?
If the fouling were soft, I would believe that an additional problem will occur when shooting just primers, because primers are not clean.. and the debris build up will naturally occur around the nose of the breech plug where there is a ledge for the primer pressure to build back on to.




